Nooooo, Tanukichi!!!
I have to grudgingly say Caribou wins this. I'm not sure Chopper has anything that can deal with a Logia user yet. Luffy only mentioned that Zoro and Sanji are Haki users. Maybe brain point can figure something out, but we haven't seen that yet. I bet he could find a weakness (and somehow not need Haki), but it would be tough for him to evade the swamp stuff in the meantime.
Maybe Chopper Mask could win, though, haha.